news

27 August 2018

Sienna Biopharmaceuticals announces result from First-in-Human Study of SNA-125 in Psoriasis and continued progression to Phase 2

Sienna Biopharmaceuticals, Inc. (NASDAQ:SNNA), a clinical-stage medical dermatology and aesthetics company, today announced results from a first-in-human study of its investigational new chemical entity SNA-125, a JAK3/TrkA inhibitor being evaluated as a first-in-class topically administered medication to treat mild-to-moderate psoriasis.

SNA-125 was developed using Sienna’s Topical by Design™ platform, which yields new chemical entities (NCEs) designed to deliver high local drug concentration in the target tissue with minimal to no systemic exposure for patients. SNA-125 selectively inhibits Janus kinase 3 (JAK3) and tropomyosin receptor kinase A (TrkA). JAK3 inhibition blocks the signaling of key cytokines, resulting in reduced severity of certain autoimmune and inflammatory diseases such as psoriasis. TrkA is the high-affinity receptor for nerve growth factor (NGF), a known mediator of neurogenic inflammation associated with psoriasis, as well as pruritus (itch).

This exploratory Phase 1/2, double-blind, within-subject vehicle-controlled study in 15 subjects, using a psoriasis microplaque model, was designed to measure an effect on inflammatory skin infiltrate thickness, local tolerability, and histology and biomarkers with two doses of SNA-125 prototype gel applied once daily for 10 days.

In this model, SNA-125, the second NCE from Sienna’s Topical by Design™ platform, was well-tolerated and showed no safety signals. Neither dose of SNA-125 (0.2 or 2 percent) reduced the inflammatory skin infiltrate thickness from baseline (p>0.8). However, histological and biomarker analyses showed a modest, statistically significant reduction with SNA-125 0.2 percent in epidermal thickness from baseline (-17%, p<0.05), as well as modulation of certain psoriasis-relevant biomarkers and gene expression profiles.

“This exploratory study, while limited, showed a modest drug effect and good tolerability with SNA-125, and provides us with directional information to help guide the design of our Phase 2 development program,” said Frederick C. Beddingfield III, MD, PhD, President and Chief Executive Officer of Sienna Biopharmaceuticals. “Of course, we would have liked to have seen more robust impact in this early-stage model, but treatment with SNA-125 may take longer than ten treatments to reveal its full effect. In parallel with this study, we have developed a more optimal cream formulation to treat inflammatory skin disorders that is undergoing nonclinical testing, and we remain excited about our Phase 2 studies beginning in the second half of 2019. We look forward to additional data from our Topical by Design™ platform in the fourth quarter of 2018 – namely, our SNA-125 Phase 1/2 study in atopic dermatitis, as well as our SNA-120 Phase 2b study in pruritis associated with psoriasis, now that enrollment has been completed ahead of schedule.”

Pipeline Overview

Sienna’s pipeline currently includes five clinical-stage programs:

(from the Company’s Topical by Design™ platform)

SNA-125 for the treatment of atopic dermatitis; Phase 1/2 results expected in the fourth quarter of 2018

SNA-125 Phase 2 studies expected to begin in the second half of 2019

SNA-120 for the treatment of pruritus associated with psoriasis and the underlying psoriasis; Phase 2b top-line results now expected in the fourth quarter of 2018

(from the Company’s Topical Photoparticle Therapy™ platform)

SNA-001 for the reduction of light-pigmented hair

pivotal results with the 1064 nm wavelength laser expected in the fourth quarter of 2018

pivotal results with the 810 nm and with the 755 nm wavelength lasers expected in the first quarter of 2019

SNA-001 for the treatment of acne

pivotal results with the 755 nm wavelength laser expected in the fourth quarter of 2018